Film cut-out



Oct. 25, 1938. L. J. BARWOOD FILM CUT-OUT 2 Sheets-Sheet l Filed Aug. 16, 1935 Oct. 25, 1938. D 2,134,392

FILM CUT OUT Filed Aug. 16, 1935 I 21 U6 :1 f0 1 L EON J. 5/112 WOOD U/Wowwiy Patented Oct. 25, 1938 UNITED STATES PATENT OFFICE 2,134,392 FILM CUT-OUT Leon Joachim Barwood, Cambridge, Mass.

Application August 16, 1935,

Serial Nb. 36,489

11 Claims. (o1. 200--1l8) The present invention relates to film cut-outs,

and its object is film cut-out that disposed in the lating member the friction of the or the conducting members against the opening being suificient together as a unit, particularly to provide a new and improved shall be simple in construction,

to hold the if the dia efiicient in operation, its dielectric characbreakdown, voltage.

tion disclosed in Letters ted September 17,

f the film cut-out are insuparts meter of the conducting members is somewhat larger than that of the ing may be torus-sh action.

An object of th an improved film cut-out character provided the torus than is Patent.

The Letters Pa cation comprisin a further object cation also.

Other hereinafter and will in the appended The invention connection with which Fig. l. is

and further obj opening. The wallof the e prese with a open aped to aid this holding nt invention is to provide of the above described greater curvature of disclosed in the said letters tent discloses also a modifig two insulating members and be particularly claims.

to improve upon this modifiects will be explained pointed out will be more fully described in the accompanying drawings, in an elevation of a film cut-out embodying the present invention; Figs..2

are diametrical sections on the lines 2-44. spectively, Fig. 3 is a view tion; Figs. the embodiment being partly broken is a view similar tion; Fig. 8 is taken upon larger of Fig. l and 4-4 of Fig.

and 4 scales 3, re-

the directions of the arrows;

Fig. l of a modificarts of shown in Figs. 3 and 4, Fig. 5

away, for clearness; to

section, but upon a larger Fig. 7 Fig. l of a further modificascale,

taken upon the line 8-8 of Fig.7, looking in the arrows; and Fig. 9 is a perspecthe modification shown in Figs.

directions of the tive of a part of '1 and 8.

As described in the said Letters Patent,

cut-out may comprise or disc-shaped, centrally and 4, of conducting ma as aluminum, but insulated desired manner.

disc-shaped, ins

a circular or As illustrated in Figs.

of tissue paper, silk or any other desired ma two preferably circular bwed-out, members 2 terial, like metal,

from each other in such lto 4,

ulating, thin film terial,

may be disposed between and separating the conducting members, so as to contact with their non-bowed-out peripheral portions, thus providing an air chamber 18 between the insulating disc 6 and the centrally-bowed-out portion of each disc 2 and 4. As illustrated in Figs. '7 and 8, however, the separating film 6 may be omitted and the contacting, peripheral, inner surfaces of the metal members 2 and 4 may be covered with a suitable insulating coating 23 of an oxide of the metal. The oxide-coating modification may be embodied also in the modification illustrated by Figs. 3 and 4. As is also described in the said Letters Patent, the discs 2 and 4 and the film (-2 may be held together mechanically, as a unit, merely by the peripheral edges of the discs 2 and 4 rrictionally engaging the torus-shaped or concave wa1l22 of the opening of a ringshaped or annular, stiff-fibre, insulating disc 8.

According to a feature of the present invention, the curvature of the torus-shaped wall 22 is considerablyenlar ged, so as substantially to increase the height of its peripheral edges or projections 24. This may be eiiected in any suitable manner, as by means of a burring roll (not shown) that moves along the exterior surfaces of the ring 8, near, and along the circumference of, the opening, to produce a groove 26, thereby upsetting or plowing up or spreading the material of the insulating ring 8 into the opening of the ring.

The grooves 26 are not cuts in the material of the ring 8. The plowing up of the material of the ring is, rather, attended by a compression of the material in the grooves 26, thus hardening and strengthening the material in the neighborhood of the edges or projections 24. The edges or projectionsneed not, of course, be continuous, they may bedisposed at a plurality of separated positions along the circumference of the opening of the ring 8. The projections 24 thus engage the conducting discs 2 and i at their sides, near their peripheries only, more positively than in the said Letters Patent to hold the discs 2 and 4 more effectively in the opening of the ring 8.

in corresponding, alined projections 28 and 30 and through recesses 39 in the insulating film 6. The rivets I6 need not members, as illustrated, but they may be formed integral with, or pressed out from, one of the discs l0 and I2.

the opening with projections between which the conducting members and the means are held toas to extend positions along its exterior surfaces near the 4. A film cut-out comprising two conducting insulating film disposed between and separating the conducting members, and a member having an opening in which the conducting and the insulating members are disposed gether as a unit in the opening.

5. A film cut-out comprising two insulated conducting members, two similar members each havsaid one member.

6. A film cut-out comprising two insulated conducting members, two similar members each having an opening and a projection extending into the opening, the projections being alined, the projections on one of the similar members having a recess, and means cooperating with the other the opening, having alined the projections being alined and recesses, and means members disposed as a unit between members and the opening.

8. A film cut-out comprising two insulated conducting members, two similar members each havextending throughcorresponding recesses for mechanically holding the similar members together with the openings opposed to each other and with the conducting members disposed as a unit between the similar members and the opening.

9. A film cut-out comprising two conducting members, an insulating film disposed between and separating the conducting members, two similarinsulating members each having a similar gether as a unit.

11. A film cu -out comprising two conducting 12. A film cut-out comprising two insulated conducting members, two similar members each having an opening and an annular recess surwith the other member and disposed in the recess for mechanically holding the ing, the conducting members having recesses for receiving the projections.

13. A method of making an insulating ring for a film cut-out comprising plowing up the material of the insulating ring into the opening of the ring.

14. A method or making a film cut-out comprising plowing up the material of an insulating ring into the opening of the ring at a plurality of positions along its exterior surfaces near the opening to provide the wall of the opening with projections, and inserting insulated conducting members in the ring to cause them to be held together as a unit in the ring by the projections.

15. A film cut-out comprising two insulated conducting members, and insulating means engaging the conducting members at their edges, and also at their sides near their peripheries only, for holding the conducting members and the insulating means together as a unit.

16. A film cut-out comprising two conducting members, an insulating film disposed between and separating the conducting members, and

LEON J. BARWOOD. 

